The CWRU Cancer Center Flow Cytometry resource is an established core that has a history of stable direction (Director: 15 years), management (6 & 7 years), NCI funding (13 years), and supporting cancer research with up-to-date, well-maintained flow cytometry and cell sorting instrumentation. The director, James Jacobberger, has a major interest in the science of Cytometry. Considered to be one of the field?s leaders, Dr. Jacobberger has a strong commitment to developing and maintaining a robust and sophisticated Flow Cytometry Core that is especially flexible and can respond to the diverse needs of the CWRU Cancer Center investigators. The manager, Mr. Sramkoski, is a trained Medical Technician, with specialization in Cytometry who is equally committed. Together they have 37 years experience in the field and provide a superior level of expertise and guidance during experimental design and protocol development. Use of the core has grown steadily for 15 years with an especially sharp increase in recent years. In any one year there are approximately 70 principal investigators (users) drawn from a base of approximately 127 active investigators who have used the facility within the first few years. (Since inception, the core has assisted 167 investigators.) The facility currently operates at full capacity with two instruments - a single laser 4 color analyzer and a 4 laser, 4 color, 6 parameter cell sorter. An order has been placed for a new Becton-Dickinson LSR analyzer with 3 lasers and 6 color capability. A grant has been submitted for an additional (high speed) cell sorter that will have 5 lasers and 8 color capacity. Acquisition of these instruments will ensure that the facility can continue to support growth of cancer research at CWRU. Since the last competitive renewal an Assistant Manager has been hired to handle the increased work load and to establish a staining service. The facility operates with planned development that does and will provide outstanding technology and science in Cytometry for the Cancer Center?s membership.